The antioxidant activity and free radical scavenging capacity of the essential oil and three different extracts of wildly grown Mentha longifolia (M. longifolia) were studied. The essential oil from M. longifolia aerial parts was isolated by hydrodistillation technique using Clevenger-type apparatus. The extracts were prepared with three solvents of different polarity (n-hexane, dichloromethane, and methanol) using Soxhlet extractor. Maximum extract yield was obtained with methanol (12.6？g/100？g) while the minimum with dichloromethane (3.50？g/100？g). The essential oil content was found to be 1.07？g/100？g. A total of 19 constituents were identified in the M. longifolia oil using GC/MS. The main components detected were piperitenone oxide, piperitenone, germacrene D, borneol, and β-caryophyllene. The total phenolics (TP) and total flavonoids (TF) contents of the methanol extract of M. longifolia were found to be significantly higher than dichloromethane and hexane extracts. The dichloromethane and methanol extracts exhibited excellent antioxidant activity as assessed by 2,2′-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging ability, bleaching β-carotene, and inhibition of linoleic acid peroxidation assays. The essential oil and hexane extract showed comparatively weaker antioxidant and free radical scavenging activities. The results of the study have validated the medicinal and antioxidant potential of M. longifolia essential oil and extracts. 1. Introduction Free radicals are considered to initiate oxidation that leads to aging and causes diseases in human beings [1, 2]. Moreover, activated oxygen incorporates reactive oxygen species (ROS) which consists of free radicals (1O2, , , ONOO？) and nonfree radicals (H2O2, NO, and R–OOH) . ROS are liberated by virtue of stress, and thus, an imbalance is developed in the body that damages cells in it and causes health problems [2, 4]. Moreover, oxidation in processed foods, enriched with fats and oils, during storage leads to spoilage and quality deterioration . The use of synthetic antioxidants such as butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT) and tertiary butylhydroquinone (TBHQ) have been restricted because of their carcinogenicity and other toxic properties [3, 6]. Thus, the interest in natural antioxidants has increased considerably. Natural antioxidants can be phenolic compounds (tocopherols, flavonoids, and phenolic acids) and carotenoids (lutein, lycopene, and carotene). Growing evidence has shown an inverse correlation between the intake of dietary antioxidants and
A. I. Hussain, F. Anwar, S. T. H. Sherazi, and R. Przybylski, “Chemical composition, antioxidant and antimicrobial activities of basil (Ocimum basilicum) essential oils depends on seasonal variations,” Food Chemistry, vol. 108, no. 3, pp. 986–995, 2008.
B. Sultana, F. Anwar, and R. Przybylski, “Antioxidant activity of phenolic components present in barks of Azadirachta indica, Terminalia arjuna, Acacia nilotica, and Eugenia jambolana Lam. trees,” Food Chemistry, vol. 104, no. 3, pp. 1106–1114, 2007.
S. A. S. Chatha, A. I. Hussain, J. Bajwa, and M. Sagir, “Antioxidant activity of different solvent extracts of rice bran at accelerated storage of sunflower oil,” Journal of Food Lipids, vol. 13, no. 4, pp. 424–433, 2006.
P. Siddhuraju and K. Becker, “Antioxidant properties of various solvent extracts of total phenolic constituents from three different agroclimatic origins of drumstick tree (Moringa oleifera Lam.) leaves,” Journal of Agricultural and Food Chemistry, vol. 51, no. 8, pp. 2144–2155, 2003.
A. I. Hussain, F. Anwar, S. A. S. Chatha, A. Jabbar, S. Mahboob, and P. S. Nigam, “Rosmarinus officinalis essential oil: antiproliferative, antioxidant and antibacterial activities,” Brazilian Journal of Microbiology, vol. 41, no. 4, pp. 1070–1078, 2010.
A. I. Hussain, F. Anwar, P. S. Nigam, M. Ashraf, and A. H. Gilani, “Seasonal variation in content, chemical composition and antimicrobial and cytotoxic activities of essential oils from four Mentha species,” Journal of the Science of Food and Agriculture, vol. 90, no. 11, pp. 1827–1836, 2010.
A. I. Hussain, F. Anwar, S. Rasheed, P. S. Nigam, O. Janneh, and S. D. Sarker, “Composition, antioxidant and chemotherapeutic properties of the essential oils from two Origanum species growing in Pakistan,” Revista Brasileira de Farmacognosia, vol. 21, no. 6, pp. 943–952, 2011.
F. Anwar, A. I. Hussain, S. T. H. Sherazi, and M. I. Bhanger, “Changes in composition and antioxidant and antimicrobial activities of essential oil of fennel (Foeniculum vulgare Mill.) fruit at different stages of maturity,” Journal of Herbs, Spices and Medicinal Plants, vol. 15, no. 2, pp. 187–202, 2009.
F. Anwar, M. Ali, A. I. Hussain, and M. Shahid, “Antioxidant and antimicrobial activities of essential oil and extracts of fennel (Foeniculum vulgare Mill.) seeds from Pakistan,” Flavour and Fragrance Journal, vol. 24, no. 4, pp. 170–176, 2009.
K. Vagionas, K. Graikou, O. Ngassapa, D. Runyoro, and I. Chinou, “Composition and antimicrobial activity of the essential oils of three Satureja species growing in Tanzania,” Food Chemistry, vol. 103, no. 2, pp. 319–324, 2007.
A. I. Hussain, S. A. S. Chatha, S. Noor et al., “Effect of extraction techniques and solvent systems for the extraction of antioxidant components from peanut (Arachis hypogaea L.) Hulls,” Food Analytical Methods, vol. 5, no. 4, pp. 890–896, 2012.
A. M. Viljoen, S. Petkar, S. F. van Vuuren, A. C. Figueiredo, L. G. Pedro, and J. G. Barroso, “The chemo-geographical variation in essential oil composition and the antimicrobial properties of “wild mint”—Mentha longifolia subsp. polyadena (Lamiaceae) in Southern Africa,” Journal of Essential Oil Research, vol. 18, pp. 60–65, 2006.
M. Gulluce, F. Sahin, M. Sokmen, H. Ozer, D. Daferera, and A. Sokmen, “Antimicrobial and antioxidant properties of the essential oils and methanol extract from Mentha longifolia L. ssp. longifolia,” Food Chemistry, vol. 103, no. 4, pp. 1449–1456, 2007.